Keyboard input display device

ABSTRACT

A plurality of multifaceted single character display elements, each of which is independently rotatable to printing, development, display-hard copy, and erasure stations in response to a keyboard input, is disclosed. The use of single character display elements together with resilient spacing means between each element makes possible line justification prior to making a hard copy.

" United states Patent Inventors David E. Damouth Rochester. N.Y.; Wilbur G. Hespenheide, Westlake Village, Calil.

Appl. No. 17,093

Filed Mar. 6, 1970 C ontinuation-in-part of Ser. No. 692.928. Dec. 22. 1967. abandoned.

July 20,1971

Xerox Corporation Rochester, N.Y.

Patented Assignee KEYBOARD INPUT DISPLAY DEVICE 4 Claims, 5 Drawing Figs.

U.S. Cl 197/1 R, 101/1, l0l/DlG. 13 Int. Cl B4 lj 3/00 Field ofSeareh l0l/DlG. l3; l97/DlG, 4

INDEXING MEANS DISPLAY AND HARD COPY STATION l56| References Cited UNlTED STATES PATENTS 1,093,831 4/1914 Cornwall l97/DlG. 4 1,484,568 2/1924 Sauage .L 197/DlG. 4 1,992,017 2/1935 Spielvogel. 197/DlG. 4 2,107,272 2/1938 A'mdur l97/DlG. 4 2,126,480 8/1938 Landsiedel 197/84 X 2,985,135 5/1961 Hickerson 101/016. 13 3,188,649 6/1965 Preisinger et al. 10l/D1G. 13 3,422,753 l/1969 Strassner et al 10l/D1G. 13

Primary Examiner-Edgar S. Burr Attorneys-Paul M. Enlow, James J. Ralabate, Ronald Zibelli and John E. Beck 1 ABSTRACT: A plurality of multifaceted single character display elements, each of which is independently rotatable to printing, development, display-hard copy, and erasure stations in response to a keyboard input, is disclosed. The use of single character display elements together with resilient spacing means between each element makes possible line justification prior to making a hard copy.

ERASlNG STATlON DEVELOPIENT STATION KEYBOARD INPUT DISPLAY'DEVICE- CROSS-REFERENCE TO OTHER APPLICATIONS This application is a continuation-in-part of application Scr. No. 692,928, filed Dec. 22, I967, the printing to'The printing same assignee as the present application, and now abandoned. BACKGROUND OF THE INVENTION In general, the present invention relates to display devices 7 and more specifically to a system for the display of alphanumeric information.

The present invention may find use as a date output display device, an electrostatic typewriter, or as a composing device for short run printing operation The prior art in this area has involved the use of optical projection devices'which require large local extcmalmcmories DESCRIPTION OF THE EMBODIMENTS OF THE PRESENT INVENTION While, for-simplicity, cubes I0 will be referred to throughout as the preferred embodiment of the multifaceted single character display element, it is clear that other polygonal elements having 5, 6, or 8 sides, etc. may be employed to permit any desired arrangement of separate corona charging, imaging, toning, display, transfer, storage, hard copy, and erasure stations.

The cubes 10 are individually free to rotate around cylindrical shaft means 12 and thus may present any one of their four sides to the front display and hard copy station 28 for viewing, projection and/or the formation of a hard copy. Each of the cubes I0 is faced on the four sides in planes parallel to the central shaft 12 with a dielectric layer on which a character pattern may be generated, toned, and erased, as desired.

Altemativelypthe faces of cubes 10 may be coated with a photoconductor which may be charged and locally discharged in image configuration by optical character masking means as well'known in the art. ln any case, the basic cube may be of a conductive material. 1

An electrographic printing head 26 indicated by the plurality of electrographic recording styli constitutes the preferred Accordingly, it is an object of the present invention to provide a new, simple, and highly effective output display device and method which overcomes the deficiencies of the prior art as described above.

It is a further object of thepresent invention to provide a display device in which the last character formed may be viewed immediatelyafter its formation for error correction.

Another object of the present invention is to provide a display device in which it is possible to justify a line before transferring it to a hard copy.

Other objects in a fuller understanding of the invention may be had by referring to the following description in claims when read in conjunction with theaccompanying drawing.

SUMMARY OF THE INVENTION development, display-hard copy, and erasure station coupled with a backspacing capability makes possible substantially instant viewing of a character after its formation and error correction, when desired.

BRIEF DESCRIPTION OF THE DRAWINGS In order to facilitate the understanding of this invention, reference will'now be made to the appended drawings of two embodiments of 'the present invention. The drawings should not be construed as limiting the invention but as exemplary 1 only. In the drawing:

which maybe used both embodiments of the present invention; and, I

FIG. 5 is a sectional view of the line justification apparatus of the present invention.

embodiment of the printing means. The printing head 26 is common to all of the cubes 10 and traverses along cylindrical shaft I4 to print out the input message on the plurality of tubes 10 under thecontrol of a suitable keyboard indexing means 24 or the like. This will be described in more detail hereinafter. The indexing means 24 normally causes the printing head 26 to progress one step at a time but spacing and backspacing keys are available to produce these operations.

The electrographic styli of printing head 26 may be in a seven pin linear array for a printout utilizing five or more indexing steps per cube, or may be a 35pin matrix.

In the alternative, the electrographic printing head may be a rotatable wheelor cylinder with fully formed characters thereon. It is, also, possible to employ various ink deposition devices, a golf ball printing head, or a chain printer which transfers an image from a ribbon.

As will be seen in connection with the description of FIG. 4, the input means 20 is preferably a keyboard input device for low speed operation, however, it may also be a data link from a computer or the like. The information to be printed will normally be derived from the output of the keyboard one character ata time and in general is assumed to be presented to the'printing head 26 one character at a time although the binary bits within a character may be in either parallel or series form.

Attached to the printing head 26 is a cursor 18 to aid in showing the operator the entry position. Such a cursor 18 is particularly useful in backspacing and error correction operations.

Printing head actuator means 16 is mounted to travel with the printing head. Means may be provided, as set forth hereinbelow with reference to FIGS. 2 and 3, to rotate each cube through a toning position at development station 30 to a viewing position at the display and hard copy station 28 immediately after the imaging operation.

Stop means 38 together with resilient means 34 and interelement resilient means 36 make format control possible by enabling individual character elements to be separated to completely fill any desired line length. The resilient means 34 and 36 may be springs or other resilient elements. In the alternative, air wedges .or similar means may be employed to control spacing. This is described in more detail in connection with no.5.

ing means 26. It consists of means well known in the xero- 4 graphic and electro'graphie arts for the development of latent At'the display and hard copy station 28 the toned image the detent arm in the direction of the recording is large may be transferred to paper or to an'offset rollfor later transfer to a hard copy medium. In addition to direct viewing,

the image maybe projected and if necessary inverted or the surface of a cube I for error correction or tootherwise prepare the surface for reimaging. In addition toanelement suitable for erasing a single cube the erasing station may comprise a means sufficient to erase an entire line at a time prior to rotation of the cubes 10 to the printing position for rermagmg. v

I The transfer and erasure stations are shown in greater detail in FIGS. 2 and 3 which will be described hereinafter.

In operation, input data from a keyboard input unit or the like is fed to a printing head'26 which deposits an electrostatic pattern of charge or otherwise marks the face of cube [0 which-is in the printing position in.a single character configuration. Means may be provided, as described hercinbelow with reference to FIGS. 2 and 3, to rotate the cube 10 just printed to the development station position 30 as the printing head 26 is indexedto the next cube It) on, which it is desired to print. The most recent character is in each case displayed for error checking and correction, if desired; Correction is made possible by the provision for backspacing and erasureof individual .characters.

Data enters at the normal left edge-and writing progresses to vthe right as viewed at the display station with each one-of the faces of the cube being made visible to'an' observer in .turn. The provision of separate cubes 10 each displaying a single character and separatedby resilient means 36 makes possible line justification for any desired length of line inexcess of the enou'gh tope rmit' noid52. 1 I

As shown in FIGS. 2 and 3, each cube 10 has had two opposite edges '54 beveled so as to avoid interference with the detent arm 42 in its restraining position. This permits each cube when its associated detent arm is raised to rotate I80". As noted in connection with the embodiment of FIG. I, there are associated with the array of cubes I0 a development station, a display-hard copystation, and an erasure station. These will now be describcdin greater detail.

As shown best in FIG.,3, a fibrous applicator 56 in the form of an elongated cylinder is mounted in a housing 58 to be driven into rotation by motive power from a source not shown butapplicd to its support shaft 60. A sump is formed at 62 in the housing 58 to accommodate a quantity of eleetroscopic marking particles which are conveyed to the applicator 56 by a suitable donor roller 64 associated with a drive shaft 66 to which suitable rotativc power may be supplied. The applicator 56 may be made, for example, form either natural fur or synthetic fibers having that particular triboelectric relationship to be used as an eleetroscopic developing means. The housing 58 assists in keeping the eleetroscopic marking particles within the developing station. As shown in FIG. 3 the a wide latitude of actuation timing of solocube I0 interferes with the periphery of the applicator 56 and if this cube 10 was to rotate 180 in a counterclockwise direction, it can be seen that the facet opposite the printing head 26 would be brought into developing contact with the applicator as it revolves in housing 58. In' this manner, the

. latent electrostatic images placed on that facet of the cube 10 physical dimensions of the cube array employed. Following the completion of these operations the cubes 10 may be rotated to the erasing station 32 where they are prepared to receive new data when rotated again to the printing station.

Reference will now be made to FIGS. 2 and 3 which illustrate another form which the present invention may take and also illustrate the developing, hard copy transfer, and erasure stations compatible with the embodiment previously described in connection with FIG. 1. As shown there are a plurality of cubes l0 fixed for rotation with shaft 12 by way of a frictional coupling collar 40 unless the cubes are restrained from rotation. During the recording and display mode they are restrained from rotation by means of a plurality of detent arms 42 which act to engage the upper left-hand corner of the cube 10 prohibiting it from turning with shaft 12. These detent arms From this description it will be appreciated thatwhen the detent arm 42 is rotated in a counterclockwise direction as used in FIG.3 about shaft 44 cube 10 will be able to rotate in a counterclockwise directionwith shaft The manner in which the detent arm may be actuated is by means of an armature element 50 whichis'rno'vcd by the'actionof a solenoid 52 mounted on the printing head 26. Several. methods may be-uscd to actually energize the solenoid. It may be done manually from the keyboard by the depression of a suitable key which simply sends a pulse to the solenoid. Alternatively,'it may be automatically actuated by suitable control circuitry which iszto be initiated at the completion of the recording of a character on a particular cube 10. The width of will be rendered visible by the transfer of such marking particles from the applicator 56 to the surface thereof.

As the cube l0 rotates its 180 the devclopedimage will end up at the display station which also represents the hard copy station. FIG. 3 as well as FIG. 2 illustrates asupply roll 68 of recording medium supported on a pulley 70 which forms a web around an idler, roller 72 and through two pinch rollers 74. Between idler roller 72 and pinch roller 74 there is positioned adjacent the path of the web a suitable fusing station 76 which may comprise a plurality of resistance heating wires of suitable design for fusing eleetroscopic marking particles into the fibers of the recording web.

As shown in FIGS. 2 and 3 there is a transfer roller 78 mounted for rotation on a fixed shaft 80. This transfer roller is prior to the webs entry to the fusing area. Two slotted brackets 82 are positioned at both sides of the array of cubes l0 and provide a guiding effect by way of the slots 86 for the transfer roller 78. The broken lines illustrate the alternate position of the transfer roller 72 and have been given the reference numeral 88. In this position the surface of the transfer roller is in contact with another fibrous cylindrical member 90 which constitutes the erasure means suitably housed in a housing .92. This erasure means is supported for rotation about a shaft 94 which is driven from a suitable source of motive power not illustrated.

The transfer roller is free to rotate about its shaft and will rotate freely under the influence of the rotating erasure brush 90. In this manner, the entire periphery of the transfer roller is cleaned'by the erasure brush 90. The transfer cycle preparatory to creating a hard copy of the displayed information may be initiated by depressing a special key on the keyboard to be described. This may cause a suitable transfer bias voltage to be applied to the-transfer roller which in turn is caused to begin its movement down through the viewing station guided bythe slots 86 in the brackets 82. The transfer roller being free to rotate about its axis is moved in slight interference with the image area of the cubes and thus as it rolls down the cubes face without slipping most of the developed image will transfer from the cube to the transfer roller. This is a'result of a 'combination of mechanical surface forces and the attraction of the biased voltage on-the transfer roller itself. At the end of the traversal of the transfer roller, it comes into contact with the recording medium supported by the idler roller 72. Appropriate limit switches may be incorporated as is well known in the art to react to the end of traversal of the transfer roller to energize the pinched rollers 74 drawing the recording medium over the idler roller 72. This movement in the recording medium also causes the transfer roller to roll in contact with it. This same limit switch may also serve the purpose of reversing the bias voltage on the transfer roller causing the transferred image to transfer from the roller to the recording medium. The relation between the transfer rollers circumference and the distance the roller travels is selected so that each line transfers to the web in proper registration relative to the previous line. After transfer, but before the nextline is composed, the transfer rollers return to the erase position as shown by the broken lines to await the next transfer. At this point, a limit switch may again be used to control the potential on the roller.

After the hard copy transfer cycle is completed it is necessary to erase the residual images remaining on the face of cubes 10. This is accomplished simultaneously with the erasure of any residual image on the transfer roller 78 by the effect of the erasure brush 90 rotating on its shaft 94.

By the suitable depression of the proper key of the keyboard, the detent arms may be uniformly actuated to permit the cubes to rotate another 180 back to their original position. During this rotation, the erasure brush 90 is in operation and sweeps the surface clean of any residual marking particles as well as neutralizing the charge triboelectrically that remained on the recording surface of the cube 10.

Additionally, the erasure brush 90 may include conductive fibers which are grounded to act as a discharge path for any residual charges on the cubes 10.

It is noted that suitable mechanical means may be provided foractuating all the detent arms 42 at the same time which may be actuated from the keyboard.

This can be accomplished simply by energizing an appropriate lever to momentarily depress shaft 45 in slot 47 as shown in FIG. 2. Shaft 45 is integral with stop member 48 for detent arms 42. As can be seen in FIG. 3, such a depression 'will pivot all the detent arms about their support shaft 44 releasing all the cubes for rotation at one time. In the alternative, each cube may be erased individually as information is recorded on another recording surface opposite the originally recorded surface. In this way each cube may be erased during the time that the new recorded information is developed and presented to the display station.

After the transfer of the developed image from the transferroller 78 to the recording medium 68, the pinch rollers 74 will eventually pull the transferred image now on the recording medium under the fuser 76 to make the image permanent on the insulating medium.

Having described the mechanical structure of the recorder and display device of FIGS. 1 and 2 of the present invention, one possible way of controlling this system will be described with reference to the block schematic of FIG. 4. What has been described as the recorder or printer is represented basically by the suitably labeled block 100. The input to the printer originates, for example, from a conventional keyboard 102 which may generate an appropriate binary code uniquely identifying the alphanumeric symbol corresponding to the actuated key of this keyboard.

This binary code, such as used in the American Standard Code for Information Interchange, is provided to the input of a conventional decoder circuit 104 which decodes the binary code to generate a character pulse on one of a series of parallel outputs indicative of the alphanumeric symbol selected at the keyboard 102. Output conductor 106 is intended to represent a number of outputs each of which would correspond to a separate alphanumeric character in the particular alphabet incorporated in the keyboard 102.

These outputs collectively provide one input to a character generator 108 which may take various conventional forms. As an example only, generator 108 may consist of a diode matrix having a number of character select input wires which corresponds to the outputs of the decoder circuit 104. These wires are selectively coupled to readout wires via diodes which are forward biased when their respective character select wire is energized. Another form which the character generator may take is a magnetic core matrix, having five columns and seven rows, wherein a particular character select wire associated with one of the outputs 106 intertwines an appropriate pattern of magnetic cores corresponding to the alphanumerical symbol to be recorded. The character generator as well as the other parts of the block diagram of FIG. 4 are not intended to from a particular part of the present invention per se and therefore are shown schematically only since will known conventional circuits may be used to provide their functions.

Output 110 from the decoder 104 simply provides a signal indicative of the fact that a binary code has been decoded in the decoder 104. In this manner, for each character entered at the keyboard 102 which effects a decoding process in the decoder 104, an output signal will be generated on conductor 110. This effectively provides a control pulse to the character generator which may initiate, for example, in the case of a magnetic core matrix, a distributor circuit which would sequentially readout each column of the core matrix at a rate correlated to the speed of the styli movement. As each column is sampled by the distributor circuit, a group of parallel outputs would be energized depending on the cores set by the character select wire. The signals on these parallel outputs would be supplied to a suitable driver stage 111 which would provide parallel recording signals to the styli array 113 via output 112.

The manner in which the signals are supplied to the recording styli as well as to solenoid 52 may be by way of a flexible cable containing the necessary leads.

Additionally, the signals present on output 110 of the decoder 104 are supplied to an index control 24 which may include a one revolution clutch or a stepping motor. The pulses at output 110 would then either engage the clutch or activate 'the stepping motor for a period of time necessary to move the stepping motor coupled to the shaft of a pulley about which is entrained a drive cord having two ends, each coupled to one side of the printing head 26. A spring return system can be used to retrace the head back to its initial point. Such drive arrangements are well known in the arts. For example, the system disclosed in U.S. Pat. No. 3,300,017, which issued Jan. 24, 1967, in the name of Z. Yazejian et al. would accomplish the proper printing head control.

Furthermore, during such retrace it may be desirable to move the conductive recording styli from contact with the cubes 10 when electrography is the recording technique used. This also has many conventional implementations, one being simply to pivot the printing head 26 about a point prior to the retrace movement. In FIG. 2, such a point may be the axis of guide shaft 51. Suitable cam arrangements can be made to move the other guide shaft 53 against the bias of spring 55 and along slot 57 to accomplish this.

Additional keys on the keyboard 102 may control other stations of the present invention. For example, one key, a transfer key, may energize output 116 to supply signals to the transfer control 118 which will activate a clutch or motor to begin the hard copy transfer operation already described. This same key can also energize the erasure brush 90 at the option of the designer or the erasure station may be allocated a separate key, or both. Therefore, output 120 may independently control the erasure station.

While being controlled by the decoding operations, the index control may also be independently controlled by the keyboard for spacing or backspacing via output 122.

keyboard 102 for independently actuating solenoid'52 for cube rotation and for depressing shaft 45 to rotate all the cubes simultaneously.

The correction operation in case .a wrong character is recorded may be accomplished in the manner to be described. The print head 26 can be backspaced one character by depressing the appropriate key on the keyboard 102. The print head is then positioned for recording on the facet of the cube which isoppositethe facet bearing the developed image of the wrong character. The correct character is entered via the keyboard and recorded on the clean facet rotating the cube to erase the facet bearing the wrong character and displaying the correct one.

FIG. illustrates how one end of shaft 12 in the embodition or material to the teaching of the invention without d ments of FIGS. 1 and 2 may look for manual justification of the recorded and displayed lines. While a manual system will be described herein, an automatic version could easily be constructed.

As noted hereinabove, each cube 10 has a recess on each side through which shaft 12 passes. Between the cubes and fitting in these recesses is a resilient space 36. As shown in FIG. 1, the left end of shaft 12 is fitted with a fixed stop 38. The right end of this shaft 12 as shown in FIG. 5 has a sliding stop or collar [28 fitted thereto with alever 130 attached to the collar. Bymeansof this lever 130, the operator can selectively slide the collar on the shaft 12. A detent block 132 mounted on the frame (not shown) supporting shaft 12 for rotation has a series of depressions 134 in one surface thereof.

, These depressions cooperate with a ball [36 biased against the and will be held there by the spring biased ball 136.

During the compose or record mode, the collar is in its leftmost position as the operator views the cubes, forcing the cubes into their compressed position. After a line is recorded,

justification is accomplished by moving the lever 130 to the right until the lastcharacter recorded is in line with the right margin. Because of the resilient spacers 36, all characters recorded will spread proportionately to fill the space between the left and right margins.

While the invention has beeiid escribed with reference to its preferred embodiments, it'will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the true spirit and scope of the invention. In addition, many. modifications may be made to adapt a particular situaparting from its essential teachings.

We claim:

l. A keyboard input display device for producing on a recording medium the characters generated by said keyboard comprising:

a. a plurality of multifaceted polygonal single character dis play elements axially mounted to rotate about a central shaft means, the face of said elements being capable of retaining an electrostatic charge pattern,

b. printing means for producing a pattern of electrostatic charge representative of a single character on one face of each of said display elements,

c. indexing means for positioning said printing means with respect to each of said display elements thereby enabling a completed line of characters to be generated,

d. actuator means for rotating each of said display elements to development and transfer stations, the electrostatic charge pattern being developed on the face of said display elements at said development station and the developed charge pattern being transferred to said recording medium at said transfer station, and

e. means for providing line justification of a completed line of characters on said display elements prior to developing said charge pattern. 7 2. The device as set forth in claim 1 further including means for erasing the faces of individual display elements whereby said display elements are prepared for receiving additional electrostatic charge patterns.

3. The device as defined in claim 1 wherein said display elements are rotated to said development and transfer stations aline at a time.

4. The device as defined in claim 1 wherein said display elements are rotated to said development and transfer stations individually a character at a time. 

1. A keyboard input display device for producing on a recording medium the characters generated by said keyboard comprising: a. a plurality of multifaceted polygonal single character display elements axially mounted to rotate about a central shaft means, the face of said elements being capable of retaining an electrostatic charge pattern, b. printing means for producing a pattern of electrostatic charge representative of a single character on one face of each of said display elements, c. indexing means for positioning said printing means with respect to each of said display elements thereby enabling a completed line of characters to be generated, d. actuator means for rotating each of said display elements to development and transfer stations, the electrostatic charge pattern being developed on the face of said display elements at said development station and the developed charge pattern being transferred to said recording medium at said transfer station, and e. means for providing line justification of a completed line of characters on said display elements prior to developing said charge pattern.
 2. The device as set forth in claim 1 further including means for erasing the faces of individual display elements whereby said display elements are prepared for receiving additional electrostatic charge patterns.
 3. The device as defined in claim 1 wherein said display elements are rotated to said development and transfer stations a line at a time.
 4. The device as defined in claim 1 wherein said display elements are rotated to said development and transfer stations individually a character at a time. 